Clearing the Maven Cache

The Maven cache, also called the local repository, is a folder on your system where Maven stores downloaded dependencies, plugins, and other build artifacts. This helps speed up project builds by reusing existing files instead of downloading them again.

• Stores all project dependencies and plugins locally
• Reduces build time by avoiding repeated downloads
• Located by default in ~/.m2/repository on your computer

Steps to Maven Project Setup and Cache Clearing

Follow below steps to set up a Maven project and clear the local Maven cache.

Step 1: Create a Maven Project

Use this command to create a Maven Project.

mvn archetype:generate -DgroupId=com.example -DartifactId=my-app -DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false

Step 2: Add Dependencies and Plugins to pom.xml

Here is an example pom.xml file:

<project xmlns="https://maven.apache.org/POM/4.0.0"
         xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="https://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example</groupId>
    <artifactId>my-app</artifactId>
    <version>1.0-SNAPSHOT</version>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.22.2</version>
            </plugin>
        </plugins>
    </build>
</project>

Step 3: Build the Project

To build the project, run the below command:

mvn clean install

Step 4: Clear the Maven Cache

To clear the Maven cache, run the below command:

mvn dependency:purge-local-repository -DreResolve=true

Step 5: Verify Project Structure

Check that the project folders are created properly (src/main/java, src/test/java).

• Ensures correct Maven standard directory layout
• Helps avoid build issues later

Step 6: Run the Application

Navigate to the main class and run it (or use command line).

mvn exec:java -Dexec.mainClass="com.example.App"

Step 7: Run Tests

• Validates application functionality
• Ensures build stability

Execute unit tests using Maven:

mvn test

Step 8: Rebuild After Cache Clear

After clearing cache, rebuild again:

mvn clean install

• Re-downloads all dependencies
• Ensures a fresh and error-free build